DU CHARBON BACTERIEN. 
497 
dowed with great mobility; micrococci , appearing as refrangent 
corpuscules O.So“ in diameter. These microbes are readily col¬ 
ored by analine violet. 
Inoculability. —Experience has demonstrated that blackleg is 
a “ morbus non recidions.” Previous experiments in inoculation 
have failed because— 
1st. Animals capable of having the disease were not used in 
the experiments. 
2d. Among the animals apt to have the disease, age dimin¬ 
ishes their receptivity. 
3d. The matter used was not always taken from virulent 
parts. 
4th. A sufficient dose was not employed. 
5th. Inoculation was made in regions little favorable to its 
evolution. 
The rabbit, the hog, carnivora and fowls are only susceptible 
under peculiar circumstances. Those animals which develop the 
virus readily are cattle, sheep, goats and the guinea pig. Very 
young calves (under three to five months) seem protected from 
moderate doses (six drops of virus), but this immunity ceases as 
they become herbivorous. Similar immunity is seen in typhoid 
fever in very young children. Willems noted the same in his 
early inoculations for contagious pleuro-pneumonia. Animals 
born and raised in an infected country have again acquired an 
immunity after about their fourth year, due to “ spontaneous ” 
inoculation. Old animals from countries free from the disease 
are susceptible. 
The bile is always rich in virulent bacteria, generally not 
% 
nucleated. 
The aqueous humor is but slightly so, while the urine has 
always proved innoxious. 
The amniotic fluid, serum and blood are variably virulent. 
The muscular pulp from a tumor is the most reliable means of 
producing the disease. The qu|jitity required is variable. Inocu¬ 
lation will rarely succeed with a lancet. When it does there is 
generally a general fever in thirty to thirty-six hours, while the 
local lesion heals. By subcutaneous injection one drop may pro- 
